Braced bed bottom or the like



March 27, 1945. M M. CUNNINGHAM 2,372,361

BRACED BED BOTTOM OR THE LIKE Filed May 26, 1941 2 Sheets-Sheet 1 o o o V.

N r o N o k 1% Q N N O N o 4Q S l E V lo N i W2 w M. M.' CUNNINGHAM BRAGED BED BOTTOM 0R THE LIKE Flevd May 26, 1941 2 Sheets-Sheet 2 March 27, 1945.

Patented Mar. 27, 1945 2,372,361 BRAcEn aan no'rroM on THE LIKE arion Morgan Cunningham, South Bend, Ind., assignor to Mishawaka Rubber and Woolcn Manufacturing Company, Mishawaka, Ind., a corporation of Indiana Application May 26, 1941, Serial No. 395,165

7 Claims.

This invention relates to bedding and analogous structures and the invention resides particularly in the construction and arrangement of a novel fabricated, resilient supporting or suspension assembly for mattresses, pads, cushions, and similar yieldable elements commonly employed to provide a cushioned surface for beds, cots, berths and the like.

'I'he present invention is an improvement in the general type of cushion supporting assembly disclosed in my co-pending application Serial No. 347,627, and is devised primarily to adapt the invention thereof for use in environments wherein the horizontal area, of the cushioning element is relatively large, as compared with that of a seat, and wherein it is desired to conserve vertical space. The invention hereof is particularly adapted to provide a resilient and flexible foundation or suspension means for the mattress in the berths of railway sleeping cars where, as is well known, vertical space is necessarily limited. It is to be understood, however, that the invention is in no wise limited to such adaptation but will find divers advantageous u ses, as will be apparent as the following detailed description of a specific embodiment unfolds.

It is a prime object of the present invention to provide a flexible, resilient supporting or suspension base for mattresses and similar cushioning elements which is sturdy and durable, yet of light weight, which occupies but a minimum of vertical space, and which is readily adaptable to various types of mounting. Y

Another object is to provide a suspension base for mattresses or cushions which affords adequate yieldability for ease and comfort, While avoiding any appreciable sagging.

A further object of the invention is to provide, in a mattress or cushion base comprising a diaphragm pre-stretched over an encompassing frame, cross braces which strengthen and rigidify the frame. yet which are depressible and do not interfere with free exibility of the diaphragm, and which occupy substantially no greater vertical space than does the frame.

With these and other objects in view, the invention consists in the construction and novel combination and arrangement of parts hereinafter fully described, illustrated in the accompanying drawings, and particularly pointed out in the appended claims, it being understood that the invention is not to be limited to the specific embodiment shown, but that various changes in the size, proportion andv minor details and arrangements claims, without departing from the spirit of the invention or sacricing any of the advantages thereof.

In the drawings: Figure 1 is a plan view of a marginal frame,

' with diaphragm removed, for a mattress supportsecured to various mountings.

of parts may be made, within the scope of the ing base embodying features of theA invention, and showing a form and arrangement of depressible transverse cross braces constituting important features thereof.

Figure 2 is a detailed plan view, on an enlarged scale, showing the preferred manner of mounting the cross braces in the framework.

Figure 3 is a vertical section on the line 3-3 of Figure 2.

Figure 4 is a vertical section on the line 4-4 of lFigure 2.

Figure 5 is a perspective view of a mattress suspension base constructed in accordance with the present invention, with a portion of the prestretched diaphragm removed.

. Figure 6 is a vertical section on the line 6 6 of Figure 5.

Figure 'I is an enlarged perspective view of a modification of one of the socket members for mounting the cross braces in the frame.

Figure 8 is a fragmentary perspective view showing a manner in which the mattress suspension base of the invention may be mounted on and anchored to a rigid foundation.

In my prior application, referred to above, I have disclosed and claimed a resilient base or support for seats and the like which comprises, speaking generally. a continuous marginal frame over which is stretched, and held taut thereby, a fabric diaphragm having a limited amount of resilience and compressibility, sufficient to afford adequate yieldability for ease and comfort, but insumcient to permit any appreciable sagging of the diaphragm. The marginal frame is adapted toxbe Due to the fact that the marginal frame may be constructed from fiat metal strip, and that the diaphragm may comprise a tightly stretched fabric with no appreciable sag, this type of resilient base is admirably adapted to serve as a cushion or mattress suspension where conservation of ve ical space is an important factor. However, in a pting the teaching of my said prior application to a base member for the support or suspension of mattresses and cushion elements of relatively great horizontal extent, as compared with a seat, a manufacturing difculty is experienced in that the stretching of the fabric diaphragm, which is.

preferably accomplished in the manner disclosed in my application serial No. 350,597, which has matured into Patent No. 2,314,318, issued March 16, 1943, on a marginal frame which includes side members of relatively great longitudiphragm and create local areas of complete un yieldability, thus rendering the assembly uncomfortable and, in fact, impractical as a mattress base or foundation.

Now the present invention eliminates the above mentioned manufacturing diiiiculty by providing transverse cross braces or struts which will hold the frame members against displacement during and after the diaphragm stretching operation, but which are so constructed and arranged that they are readily free to yield downwardly upon the application of depressive forces from above, and to return to their normal position substantially in the plane of the diaphragm and marginal frame upon the removal of such forces.

Referring to the drawings wherein there is seen a specific embodiment of the invention, Figure 1 shows the marginal frame for a mattress base completely assembled with the novel cro'ss bracing arrangement hereof, and ready for the application and stretching of the fabric diaphragm which is preferably applied in accordance with the teaching of my application Serial No. 350,597, which has matured into Patent'No. 2,314,318, issued March 16, 1943 mentioned above. In the illustrated embodiment, a continuous marginal frame is provided by opposite side members II) joined at their respective ends by the end frame members II. The side and end frame members are preferably formed of relatively thin -flat strip metal and it will be noted that the side members IIJ are of considerable longitudinal extent so as to form a rectangular frame having the approximate horizontal area of the average mattress for sleeping purposes. This marginal frame is adapted to be embedded in a taut fabric diaphragm prestretched thereon preferably in the manner taught in my two prior applications above identifled. Under the lateral tension applied to the side members I0 in the'diaphragm stretching operation, and the tension exerted by the tautly stretched diaphragm thereafter and before the assembly is anchored on a rigid foundation, these frame members have a, tendency to bow inwardly or be otherwise distorted out of their desired condition. To-overcome this difficulty, the present invention provides cross braces or struts I2, the opposite ends of which abut against the inner edges of the side frame members I0 and hold the same securely and rigidly against any displacement tendency. On the other hand, the construction and arrangement of the cross braces I2 is such that they are free to yield downwardly under the influence of depressive forces from above when the completed structure is in use as a mattress suspension.

To this end, the struts I2 are not attached to the frame members ID, but are held in proper joints which allow displacement of the respective ends of the cross braces away from their adjacent side frame members when the cross braces are bowed or sprung downwardly. To furnish this slip joint connection, there is provided a bracket I3 which is securely attached to a frame member by welding, riveting, or in other suitable fashion. The bracket I3 carries, preferably integral therewith, a tubular extension in the form of a socket I4 which extends inwardly from the respective frame member at one side of the bracket I3. The socket I4 is flattened in cross section, as clearly seen in Fig. 3, and is of a size and shape to snugly but slidably receive an end of a cross brace I2. The upper outer face of the socket portion I4 is flush with the upper surface of the bracket member I3 and, in fact, is preferably an integral continuation or extension thereof. Thus, the socket I4 `underhangs the bracket'member I3 so that the socket, which is open at both ends, lies in the same plane with the side frame member to which the bracket is attached. When two of these sockets are bracketed in alignment to opposite frame members II), and the opposite ends of a cross brace I2 inserted within the respective sockets, the said ends of the cross brace will abut and bear against the inner edges ofthe respective side frame members I0 and afford a positive brace against bowing or inward displacement of the side frame members when lateral inward tension is exerted thereon.

Although the socket members I4 and their attaching brackets I3 can be fashioned in any desired manner, I prefer to form the same in a simple and economical manner from a single fiat metal blank. Thus, it is practical to slit a metal blank inwardly from opposite edges a sufcient distance to leave an unslit portion providing an integral extension from the bracket portion I3 of approximately the same width as that of a cross brace I2. The wings I5 thus created by the slitting operation are then folded down and under, after being sheared to an appropriate length if necessary. and then soldered or welded together at their meeting edges as indicated at I6,- to form the attened socket member I4. The shape and size of the socket I4 can of course be readily controlled to accommodate any desired type of cross brace.

In mounting or bracketing these sockets or slip joints on the frame members, the under face of the bracket portion I3 is preferably spot welded to a frame member I0 as indicated at I'I, with the socket portion I4 underhanging the bracket section and arranged contiguous to the frame member. Thereafter the bracket portion I3 is preferably securely joined to the frame member by means of a continuous weld as indicated at 22.

While these manners of forming the .slip joint or bracket and socket arrangement and of attaching the same to the frame members, are those preferred by me, it is to be understood that the device may be fashioned in any other suitable manner and attached to the frame memv bers by any convenient and suitable means. The cross braces I2 preferablyl have their ends inserted into the sockets I4 before the same are bracketed to the frame members.

In producing the mattress or cushion base of the present invention, the marginal frame, such as provided by lside members III and end members II, is assembled with cross braces I2, prefrelation with respect thereto by means of slip il erably two in number arranged as Seen in Figs. 1

and 5, suitably positioned between opposite frame members III by means of opposed pairs of slip joints or sockets I 4, all in the manner just described. The assembled framework, `as seen in Fig. l, is then ready for the stretching and securing of a taut diaphragm thereon. This diaphragm is preferably in the form and arrangement disclosed in my said application, Serial No. 347,627, and comprises two sheets or layers I8 and I9 of strong relatively non-stretchy fabric, such as duck or canvas, which are adhesively joined to one another and secured in a tightly stretched condition to the frame, with the frame members I and. II and the cross braces I2 received therebetween and Ithus embedded in thel resulting two-ply diaphragm. As disclosed in my two aforesaid applications, the fabrics I8 and I9 before assembling, are frictioned on their inner faces with rubber compound preferably calendered and thus pressed into the fabric interstices and securely bonded to the fabric threads.

A gum coating is then applied to the inner fricl tioned face of each fabric and the two fabrics are then placed with their coated sides in face to face relation on either side of the assembled framework with the same thus embedded therebetween. The guml coatings are preferably of a sufficiently tacky nature so that they will readily adhere to one another upon pressing the two fabrics together. This laminated diaphragm. with the frame members I0 and II and cross braces I2 and their respective slip joints embedded therein, is then stretched taut on the frame, preferably in the manner disclosed in my said application, Serial No. 350,597, which has matured into Patent No. 2,314,318, issued March i6, 1943, after which the whole assembly is vulcanized. This operation inseparably joins the two fabric layers into a substantially integral diaphragm tautly stretched over the framework and cross braces with the same embedded therein, as clearly seen in Figs. and 6 of the dra-wings. Preferably the fabric layers should extend outwardly a short distance beyond the marginal frame as indicated at 20, so that the layers are vulcanized together both inside and outside of the frame. In addition, these layers, if desired, may be stitched together close to the frame members III and II along the inside and outside thereof, and also along opposite edges of the cross braces I2 -to provide additional strength. It will thus be seen that there is provided a thin fiat mattress or cushion base comprising a l diaphragm tautly stretched on a marginal frame of substantial longitudinal extent and that the side members of said frame are securely braced against bowing or inward displacement tendencies exerted by the diaphragm stretching operation and in fact by the completed diaphragm itself before the assembly is anchored on a cradling foundation in a manner presently to be described, due to the fact that the vulcanization contributes an increased tension of the fabric. 'I'his diaphragm, while sufficiently tensioned to avoid any appreciable sagging, is of a nature such that it possesses adequate yieldability for ease and comfort when used as a mattress base. The hereinbefore described slip jointed arrangement of the cross braces I2 allows these cross braces, which are preferably made of tempered spring steel, to bow or spring downwardly commensurate with the yieldability of .the diaphragm because of the fact that the ends of the cross braces are free to move within their sockets it away from the respective side frame members I0. Thus, the cross braces I2 in no wise interfere with the compressibllity of the diaphragm as a whole, and do not produce local areas of iiicompressi'bility. Due to their spri-xigy character, they .readily return to normal at and horizontal position u pon the removal of pressure thereon.

In utilizing the structure of the present invention as a base ,for mattresses in a bed, berth, or the like, it is wise, although not necessarily requisite, to arrange the positioning and spacing cf the cross braces I2 in a manner so that one willV -lie at approximately the waist line of an average size person and the other at approximately the knees. Thus, these braces will fall at localities which will not interfere with comfort even in the remote event that they are at all inoticeable to a person recumbent upon the matress.

It will be understood that the slip joint member, comprising the integral bracket and socket I3 and I4, is preferably formed of relatively light-weight metal having substantial flexibility. When a strut I2, engaged at either end in a socket I4, is bowed or sprung downwardly, the socket members I4 will be enabled to bend slightly at their line of juncture with the bracket sections I3, in order that the respective ends of the struts may freely slide or slip within the sockets I4, thus eliminating any tendency of the strut to bind or jam within the sockets. Upon removal of depressive forces from the assembly, the resilience of the diaphragm and the springy character of the struts I2 return the diaphragm and the struts to their normal substantially fiat condition, any tendency of the strut ends to bind or jam within the sockets I4 being obviated by the ability of the said sockets to bend at their line of,A juncture with the bracket portions I3.

In the eventY it is desired to give more free play to the socket portions I4 with respect to the bracket elements I3, or should it be desired that these elements be constructed of heavier or less flexible material, the structure and, arrangement illustrated in Fig. 7 may be utilized. In this figure there is seen a fragment of one of the side frame members I0 to which is secured, preferably by spot welding 2I and continuous welding 22, as in the manner previously described, a. socket attaching bracket 23. In this embodiment, however, the attaching bracket and the socket portion are not 4integral but are separate elements, the socket 24 being Acarried by the bracket 23 through a hinge connection. To this end the bracket 23 may be provided with a pair of laterally projecting hinge sleeves 25 spaced to receive therebetween a complementary laterally projecting sleeve 26 formd on the socket 24. A hinge pin 21 extends through the respective alined sleeves 25 and 26 and serves to hingedly connect the socket 24 with the attaching bracket 23. Thus, in this embodiment of the invention, the socket 24 has free play or movement with respect to the attaching bracket 23 and side frame member I0. Oppositely disposed slip-joint arrangements of this Fig. 7 will serve to position struts I2 with their ends in the desired abutting relation with respect tothe side frame members Iii, but are freely movable downwardly in response to flexure of the struts and freely returnable to a substantially horizontal position upon deiiexuie of the struts. This hinged mounting of the sockets is of particu-lar advantage where a heavier or stronger construction is desired or where struts are utilized of a, character having insuicient springiness to bend an integrally SUDDOYd socket, such as the socket Il, back into normal horizontal condition.

As hereinbefore explained, the mattress or cushion suspension assembly of the present invention is adapted to be manufactured and distributed as a complete unitary entity, to be subsequently mounted or cradled upon a relatively rigid foundation, such as the bed spring `sup-.- porting marginal framework of a bedstead or the like, or the marginal framework or sills of a sleeping car berth or the like. When ultimately installed the mattress base hereof is adapted to be secured or anchored on such a rigid foundation at spaced points along the side members l and end members Il, and for this purpose bolt holes or openings 21 may be provided in the side and end frame members in sufficiently close spacing arrangement to hold these frame members against inward yielding.

A manner in which the mattress suspension assembly hereof may be anchored to a permanent foundation is seen in Fig. 8 wherein the reference numeral 28 indicates the longitudinal side sills and the numeral 29 the transverse end sills of a firm and rigid foundation uponA which the mattress suspension assembly hereof may be cradled. This foundation framework may be that of a bedstead or cot and supported upon suitable legs, not shown, or it may constitute the marginal framework of a sleeping car berth. It will be understood, of course, that the mattress suspension assembly is of a suitable outline -and size to correspond with the outline of the foundation framework defined by sills 28 and 29, so that when in position thereon, as seen in Fig. 8, the side and end frame members' I0 and Il of the mattress suspension assembly rest upon and engage thatY respective side and end sills of the cradle foundation. Suitable bolt holes or openings are provided through the horizontalhr arranged flanges of the side and end sills 28 and 29, these sills herein being shown to take the form of angle irons, and these bolt holes are arranged to coincide with the bolt holes 21 in the marginal frame of the mattress suspension assembly. Bolts 30, through the registering bolt holes, rmly and securely anchor the mattress suspension assembly upon the cradling foundation. A suitable mattress or cushion is then intended to be placed upon the thus anchored suspension assembly which, due to the aforementioned resilience and compressbility of the diaphragm, and the ability of the struts I2 to bow downwardly, serves the purpose of a spring suspension for the mattress, having adequate yieldability for ease and comfort, while at the same time occupying but a minimum of vertical space.

It will be appreciated that, once the mattress base of the present invention is firmly anchored on a rigid foundation as explained above, the necessity of cross-bracing the side frame members l0 by means of the struts I2 substantially disbase which is economical and of light weight, yet sturdy, which has no appreciable sag but possesses adequate yieldability for ease and comfort, and which is cross-braced against lateral distortion, the cross braces, however, not adding to the vertical space occupied by the assembly and being freely depressible, thus not interfering with the yieldability of the mattress supporting diaphragm or detracting from the ease and comfort afforded by the same.

As hereinbefore brieiiy mentioned, one im' portant application of the mattress or cushion suspension base of the present invention, is in the berthsl of railway sleeping cars. The present mattress base or suspension is especially advantageous in a new type of railway sleeping car, wherein sleeping accommodations are arranged in tiers of three vertically spaced berths. Obviously, in such an arrangement, vertical space is at a premium. The mattress base of the present invention is manifestly of considerable value. in such an anvironment because it occupies normally no greater vertical space than the thickness of the fiat marginal frame and surrounding diaphragm, has little appreciable sag, and yet offords adequate yieldability for ease and comfort, particularly whenused for the support of a foam rubber mattress of about three inches in thickness. In such an environment, the present mattress base is adapted to be supported by bolts through suitably spaced bolt holes in the marginal frame members I0 and Il, or in other suitable manner at points about eight inches apart inthe berth framework. If desired, an upholstery-fabric may be applied over the diaphragm at the underside of the mattress base to present an attractive appearance to an occupant in the berth below. v

Thus, the present mattress or cushion base has 40 been found particularly valuable for sleeping cars as just pointed out. It is obvious, however, that its use is not all so limited, but the features thereof may be utilized as a mattress or cushion suspension in practically any similar structure designed for recumbeney and relaxation such as appears, since the mattress base is thereafter held against any lateral distortion by the rigid foundation. The springy struts, however, do assist in returning the diaphragm to its normal flat condition upon the removal of depressive forces, and contribute toward assuring the absence of any apprecibale sag in the diaphragm. These crossbraces, moreover, are an invaluable factor in the construction of a mattress or cushion suspension assembly of the general type shown herein, enabling the use of very thin, light weight strip metal for forming the marginal frame. 'I'here is thus made possible the production of a mattress cots, beds, sofas, and the like.

While I have shown and described herein a specific embodiment of my invention and a manner of producing the same it is to be understood that the invention is not limited to such specific embodiment, and other adaptations thereof, within the scope of the appended claims, will be obvious to those skilled in the art. Itwill be appreciated, moreover, that I have devised herein a novel manner and means of providing cross braces in a frame. It will also be appreciated that my 'invention includes, in a broader sense, a resilient mattress suspension or base comprising a diaphragm tautly stretched on a marginal frame and having cross braces which hold the frame against inward distortion but are freely depressible outl of the plane of the said frame so as not to interfere with the yieldability of the diaphragm. The illustrated embodiment shows the best construction and arrangement. now known to me, but other forms are possible within the scope of the invention, which includes any hform of reinforcing wherein cross braces hold the marginal frame against inward distortion but are depressible out of the plane of the frame.

What is claimed is:

1. In a mattress base or the like adapted to be attached to a rigid bedstead or the like, a marginal frame, a flexible diaphragm prestretched on said frame and held taut thereby, a resilient strut extending between opposite sides of said frame substantially in the plane thereof and bracing said sides against normal inward displacement, and means normally maintaining the ends of said strut in abutting relation with respect to said sides but'permitting displacementl of said ends inwardly of said frame and away from said sides whereby said strut may be bowed out of the plane of said frame.

2. In a cushion base or the like adapted to be attached to a rigid bedstead or the like, a marginal frame, a exible diaphragm prestretched on said frame and held taut thereby, slip joint ttings attached to said frame on opposite side members thereof and a resilient strut having its ends loosely supported by said ttings and bracing said sides against normal inward displacement, said strut being depressible out of the plane of said frame.

3. In a cushion base or the like adapted te `be attached to a rigid bedstead or the like, a marginal frame, a flexible diaphragm prestretched on said frame and held taut thereby, sockets bracketed to opposite side members of said frame and disposed inwardly thereof, and a resilient strut extending between said opposite side members and bracing the same against normal inward displacement, said strut having its ends loosely received within said sockets whereby said strut may be bowed out of the plane of said frame.

4. In a cushion base or the like adapted to be attached to a rigid bedstead or the like, a marginal frame, a exible diaphragm prestretched on said frameand held taut thereby, sockets bracketed to opposite side members of said frame and disposed inwardly thereof, and a resilient spring strut extending between said opposite side members and bracing the same against normal inward displacement, said strut having its ends .loosely received within said sockets and free to be sprung out of the plane of said frame and to return thereto.

5. In a cushion base or the like adapted to be attached to a rigid bedstead or the like, a manginal frame, a flexible diaphragm prestretched on said frame and held taut thereby, sockets hingedly bracketed on a horizontal pivot to opmsite side members of said frame and disposed inwardly thereof, and a resilient spring strut extending between said' opposite side members and bracing the same against normal inward displacement, said strut having its ends loosely received within said sockets and free to be sprung out of the plane of said frame and to return thereto.

6. A bed bottom or the like adapted to be attached to a rigid bedstead or the like comprising a ilexible deck secured to a surrounding marginal frame, and resilient bracing means interposed between and separating opposite sides of the frame and lying substantially in the plane of the deck, said bracing means having ends slipjointedly connected with said sides of the frame.

7. A bed bottom or the like adapted to be attached to a rigid bedstead or the like comprising a flexible deck secured to a surrounding marginal frame, sockets bracketed to opposite sides of said frame and extending inwardly thereof, and resilient bracing means interposed between and separating the said opposite sides of the frame and normally lying in the plane of the deck, said bracing lmeans having ends slidably received within said sockets and abutting said frame sides when said bracing means is unilexed.

MARION MORGAN CNNINGHAM. 

